i7-2600k, Asus P8P67 Pro, G.Skill F3-12800CL8D-8GBXM (2 kits for 16GB), MSI GTX580, Asus Essence STX, EMU 1212m, Silverstone SST-ST75F-P p/s, Thermalright Silver Arrow -- all stuffed into a Silverstone FT-02B case.
To test, I put my 580 back to stock speeds, and ran the only benchmarks I have: unigine heaven, dirt2, and one of the benchmarks that comes with Civ5. All the numbers were lower (I didn't write down the x8 numbers.) The one that really nagged at me was unigine heaven - which dropped from a very consistent 49.5 average fps to the low 40's. (It was consistent over 3 runs.) The others were less significant (or less consistent over multiple runs.)
I'll admit it wasn't a scientific or very well controlled test, and not one I'd want to publish in any type of review, but it was enough for my own personal use and enough to sway my own opinion.
I ended up taking the xonar essence STX out of the machine and I'm using the on board realtek sound for now. I'm hoping that the next round of P67 (or Z68) m/b's have more PCIe options for those of us trying to leave legacy PCI behind. (The irony is that the Essence STX board is actually a PCI board with an extra chip bridging it to the PCIe x1 interface... the same is true for my EMU 1212m sound card.)
Take care
Gary
i7-2600k, Asus P8P67 Pro, G.Skill F3-12800CL8D-8GBXM (2 kits for 16GB), MSI GTX580, Asus Essence STX, EMU 1212m, Silverstone SST-ST75F-P p/s, Thermalright Silver Arrow -- all stuffed into a Silverstone FT-02B case.
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